diff --git a/README.adoc b/README.adoc
index ecfb397..870f84d 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1,7 +1,8 @@
 = Contaminate
 
 Contaminate is a caching proxy masquerading as Docker registry. It can modify
-Docker images and manifests on the fly, for those who need a little more mutability in their immutable infrastructure.
+Docker images and manifests on the fly, for those who need a little more
+mutability in their immutable infrastructure.
 
 
 == Configuration
@@ -14,14 +15,17 @@ environment variables which can override configuration values.
 [cols="^1,<.^4,^1,^1"]
 |===
 .^| Name
+.^| Env Variable
 .^| Default Value
 .^| Notes
 
 | `layers_dir`
+| `CT_layers_dir`
 | `./layers.d`
 | A directory containing the layers to override on images passing through Contaminate.
 
 | `registry`
+| `CT_registry`
 | https://registry-1.docker.io
 | A Registry HTTP V2 compliant URL, reachable by Contaminate.
 
@@ -40,13 +44,9 @@ environment variables which can override configuration values.
 | `warn`
 | Log level for Contaminate logs to be printed
 
-| `CT_layers_dir`
-| `./layers.d`
-| A directory containing the layers to override on images passing through Contaminate.
-
-| `CT_registry`
-| https://registry-1.docker.io
-| A Registry HTTP V2 compliant URL, reachable by Contaminate.
+| `RUST_BACKTRACE`
+| `0`
+| Print full stack traces when errors occur
 
 |===
 
@@ -67,3 +67,12 @@ Running a local Docker registry to contaminate:
 ----
 docker run --rm -ti -e REGISTRY_HTTP_SECRET=secret -p 5000:5000 registry:2
 ----
+
+Pull some upstream images and push them into your registry
+
+[source,sh]
+----
+docker pull alpine:latest
+docker tag alpine:latest localhost:5000/library/alpine:latest
+docker push localhost:5000/library/alpine:latest
+----
diff --git a/src/main.rs b/src/main.rs
index 2b14403..c83042b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -174,6 +174,7 @@ async fn fetch_digest(req: Request<AppState>) -> Result<Response, tide::Error> {
         let accepts = header_as_str(&req, "Accept", "");
 
         if let Ok(mut up_req) = make_get_request(&full_url, &token, &accepts).await {
+            // TODO: Safely handle this error on deserialization
             let manifest: models::Manifest = up_req.body_json().await.expect("Failed to parse response");
             debug!("Manifest: {:?}", manifest);
             Ok(Response::new(200))